The Mount St. Mary's Archives and Department of Special Collections collects, arranges and preserves the evidence of the founding, development and growth, purposes, significant decisions, activities, philosophy, programs, and policies of the university. The Archives maintains the historical record of the institution's founders, faculty, supporters and alumni, as well as the community of which it is a part. It supports the mission of the university by describing these records and artifacts and making them available to faculty, administrators, seminarians, students, alumni and the community.

The Archives collects records documenting the activities, decisions, policies and programs of faculty departments and administrative offices. It also collects the personal papers of prominent officers, faculty and alumni. It serves as a resource for information on the history of the university, the local community, and the practice of Catholicism in Maryland in general and northwestern Maryland and south-central Pennsylvania in particular. The Archives collects artwork and artifacts associated with the university and its faculty, alumni and supporters, and with the history and practice of Catholicism.